1. Field of Invention
The present invention relates, in general, to a pedal effort adjusting apparatus of an accelerator pedal, which can adjust the pedal effort of an accelerator pedal in response to a simple manipulation of a user.
2. Description of Related Art
FIG. 1 illustrates an example of conventional accelerator pedals of vehicles. As shown in FIG. 1, the conventional accelerator pedal includes: a pedal housing 1 that is fixedly mounted to a body panel placed below a driver's seat; a pedal arm 2, a first end of which is provided with a pedal pad 2a, and a second end of which is inserted into the pedal arm housing 1 and is mounted such that the pedal arm 2 can be rotated relative to the pedal arm housing 1; a spring plate 3 that is mounted to the second end of the pedal arm 2 placed inside the pedal aim housing 1; a friction shoe 4 that is mounted to the end of the pedal arm 2 placed in the pedal arm housing 1 and comes into frictional contact with the inner surface of the pedal arm housing 1 when the pedal arm 2 is rotated; and an elastic member 5 that is installed in such a way that a first end thereof is supported by the spring plate 3, and a second end thereof is supported by the inner surface of the pedal arm housing 1 which faces the spring plate 3, wherein the elastic member 5 comprises an inner spring 5a and an outer spring 5b. 
When the pedal arm 2 of the conventional accelerator pedal having the above-mentioned construction is rotated around the hinge shaft 2b, the sum of a reaction force of the friction shoe 4 that comes into frictional contact with the inner surface of the pedal arm housing 1 and a reaction force that is generated by elastic compression of both the inner spring 5a and the outer spring 5b forms a pedal effort that is applied to the pedal arm 2.
However, the conventional accelerator pedal is problematic in that, when the pedal effort is too high, a driver is required to apply a high level of force to the pedal arm 2, and so the driver may easily feel fatigue from repeated manipulation of the accelerator pedal, and when the pedal effort is too low, the driver may not efficiently sense the feeling of accelerator pedal manipulation. In an effort to solve the problems, vehicle manufacturing companies in various countries manufacture vehicles in which the accelerator pedals have been completely assembled with fixed pedal effort characteristics so as to meet the respective safety laws and regulations of the various countries.
However, the conventional accelerator pedal that has been completely assembled with fixed pedal effort characteristics is problematic in that it is impossible to adjust the pedal effort, and so the accelerator pedal having the fixed pedal effort characteristics may not be used ubiquitously.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.